This application claims the priority benefit of Taiwan application serial no. 90207251, filed May 04, 2001.
1. Field of Invention
The present invention relates to a quick-release hook. More particularly, the present invention relates to an easy to operate quick-release hook.
2. Description of Related Art
In moving, transporting or stationing a heavy object, a releasable hook is often employed so that the heavy object is linked to a carrier for easy maneuver. Currently, most releasable hook has a main body, a releasing rod and an L-shaped latching hook. To latch up the hook, one hand has to grasp the main body while the other hand moves the L-shaped latching hook through the heavy object and jerks up the hook to snap into the main body. Similarly, to release the hook, one hand has to grasp the main body while the other hand triggers the releasing rod so that the L-shaped latching hook is released from the main body. Such latching and releasing method is clumsy to operate.
FIG. 1 is a schematic diagram of a conventional releasable hook. As shown in FIG. 1, a conventional releasable hook has a main body 40, an L-shaped latching hook 42 and a releasing rod 48. The main body 40 has a fastening hole 46. To operate the latching mechanism of this releasable hook, one hand has to grasp the main body 40 while the other hand grips the L-shaped latching hook 42 to hook up a heavy object. Thereafter, the L-shaped latching hook 42 jerks up quickly so that the L-shaped latching hook 42 snaps into the main body 40. To release the hook, one hand has to grasp the main body 40 while the other hand operates the releasing rod 48. Ultimately, the L-shaped latching hook 42 moves away from the main body 40 releasing the heavy object.
Major drawbacks for this type of releasable hook includes:
1. The operator has to use both hands to hook up with a heavy object or to release the hook from a heavy object. One hand is required to grip the main body while the other hand is required to snap the L-shaped latching hook onto the main body.
2. When the L-shaped latching hook is hooked onto a heavy object, a quick upward jerking motion is required to lock up the hook with the main body. Hence, the operator needs to provide extra force at this point.
Accordingly, one object of the present invention is to provide an easy to use and strength-saving quick-release hook.
To achieve these and other advantages and in accordance with the purpose of the invention, as embodied and broadly described herein, the invention provides an easy to operate quick release hook. The quick-release hook comprises of a latching hook locker, a spring, a pair of latching hooks, a pull lever and a main body. One end of the latching hook locker is shaped into a cylinder and the other end is shaped into a truncated cone or frustum. The latching hook locker also has a groove slot on the side of the cylinder section close to the frustum. The spring is attached to the cylindrical end of the latching hook locker. The two latching hooks each has a U-shaped profile and is in contact with the frustum of the latching hook locker. One end of the pull lever has a protruding section for inserting into the groove slot of the latching hook locker. The main body encloses the latching hook locker, the spring, the pull lever and the two latching hooks but exposes a portion of the two latching hooks and a portion of the pull lever. The main body has a fastening hole for fixing the quick-release hook. A protruding section of the pull lever is enclosed inside the main body and attached to the main body using a dowel pin. The other end of the pull lever is a free end capable of rotating in an arc. The free end of the pull lever has a hole. One end of each latching hook is enclosed inside the main body and attached to the main body using a dowel pin. The other end of the latching hook is a free end capable of rotating in an arc. The free end of each latching hook has a protruding section that overlaps to form a tight junction when the two latching hooks are pressed together.
The quick-release hook according to this invention may include a plurality of steel balls. Furthermore, the cylindrical side surface of the latching hook locker may include a plurality of recess cavities. The steel balls are placed inside the recess cavities in contact with the main body so that the latching hook locker is able to slide smoothly inside the main body.
The quick-release hook of this invention further includes a safety pin. In addition, the main body and the free end of the pull lever each has a safety pin hole. When the protruding section of each latching hook overlaps, the two safety pin holes are on top of each other. The safety pin may be inserted through the overlapping safety pin holes so that the pull lever is stationed relative to the main body. Hence, the free end of the pull lever is no longer free to rotate.
This invention utilizes the contact between the frustum of the latching hook locker and the two latching hooks, the compressive force provided by the spring and the contact of the steel balls inside the latching hook locker with the main body to provide a quick-release hook that can be operated single-handedly. In fact, only a thumb and a forefinger are required to tighten the free end of the two latching hooks together. This is a big improvement to the dual-hand operated conventional latching hook.
The specially designed contact between the frustum of the latching hook locker and the two latching hooks as well as the contact between the steels balls within the latching hook locker and the main body according to this invention facilitates the meshing of the free ends of the two latching hooks together to form a latching ring. Unlike a conventional latching hook design that demands a large upward jerking force to lock up the hook, only a force large enough to overcome the compressive force of the spring is required.
It is to be understood that both the foregoing general description and the following detailed description are exemplary, and are intended to provide further explanation of the invention as claimed.